High tension electric insulator and method of coating same



March 3, 1942.

L. J. DYKSTRA ETAL HIGH TENSION ELECTRIC INSULATOR AND METHOD OF COATING SAME Filed Sept. 17, 1940 INVENTORS.

mac/e Patented Mar. 3,1942

' HIGH TENSION ELECTRIC INSULATOB AND METHOD O1" COATING SAME Laurence J. Dykstra and Edwin M. Meyer, Rochester, N. Y., assignors to Victor Insulators, Inc., Victor, N. Y.. a corporation of New York Application September 17, 1940, Serial No. 351,163

12Claims.

This invention relates to a high tension electric insulator and method oi coating the same, and has for its object to afford a conducting coating on an insulator which shall be of such character as to prevent radio interference and noises resulting therefrom, while also afi'ording an iridescent porcelain surface that can be used as a road marker or for other purposes.

The invention has for a further object to provide a porcelain or silica-containing insulator body with a surface conducting coating of antimony which can be applied in a practical manner, enabling the manufacture of such an insulator at a reasonable cost.

Another purpose of the invention is to provide on a porcelain or other silica-containing body a coating of antimony that is bonded intimately thereto, becoming an integral part of the porcelain structure and not subject to attack or wear, so that the conducting coating will have an active life as long as that of the porcelain body itself.

To these and other ends, the invention consists in the construction and procedure that will appear clearly from the following description when read in conjunction with the accompan 8 drawing, the novel features being pointed out in the claims following the specification.

The drawing is a sectional view of a conventional type of insulator having a coating applied thereto in accordance with a preferred embodiment of the invention.

In the drawing, I designates an insulator body of porcelain or other silica-containing material, and 2 designatesa conducting coating of antimony.

In carrying out th invention, the insulator body, which is preferably of porcelain, is first completed and subjected to the usual firing or heat treating processes that are conventionally used in the manufacture of porcelain insulators, the insulator surface being coated with the usual silicate glaae before firing, or not, as desired. The insulator body thus constructed and heat treated is placed in a furnace and heated gradually over a period of approximately four hours from a normal room temperature to a temperatureof 1250' I". to 1300 1",, which is the approximate melting point of antimony, such gradual increase in temperature of the porcelain being efiective to prevent fracturing or damaging the porcelain due to subjecting it suddenly to excessive heat.

When the porcelain body has been brought to a temperature such as described, antimony in a volatile state is applied to its surface in any suitablemanner, or the molten antimony in a liquid state is sprayed on the surface to be coated, or the antimony is applied by maintaining the insulator in the presence of an atmosphere containing volatile antimony for a proper length of time.

Th molten antimony .is sprayed, or volatilized on the surface of the heated porcelain body in a furnace in the presence of a reducing atmosphere, which may be created by charging the furnace with charcoal, in order to prevent oxidation of the antimony. The porcelain body is preferably retained in the furnace in the presence of the volatile or sprayed antimony for a period of from forty-five minutes to one and onequarter hours, causing th antimony to form an intimate and integral molecular union with the surface of the silica-containing or porcelain body, the antimony thus remaining in a metallic state and functioning as a conductor over the surface of the insulator. It will be understood that the insulator body may be suitably masked to protect any portion of its surface, so that only the selected and exposed portion is subjected to a coating such as described.

I While the invention has been described with relation to the particular method set forth, it is not confined to the exact procedure herein described, and this application is intended to cover any modiflcationsor departures coming within the purposes of the invention and the scope of the following claims.

We claim: 1. A high tension electric insulator comprising a silica-containing body and a coating of antimony having an integral molecular union with the insulator body.

2. A high tension electric insulator comprising a porcelain body and a coating of antimony having an integral molecular union with the insulator body.

3. A high tension electric insulator comprising a procelain body having a silicate glaze and a coating of antimony having an integral molecular union with the silicate glaze.

4. The method of coating a silica-containing insulator body which consists in first firing the insulator body, then heating the insulator body to the temperature of the melting point of antimony, and applying antimony in a fluid state to the insulator body while the latter is maintained at said temperature of the melting point gooangmony, approximately from 1250 l. to

5. The method of coating a porcelain insulator body which consists in first firingthe insulator body, then heating the insulator body to the temperature of the melting point of antimony, and applying antimony in a fluid state to the insulator body while the latter is maintained at said temperature of the melting point of antimony, approiimately from 1250 F. to 1300 6. The method of coating a porcelain insulator body having a silicate glaze thereon which consists in first firing the insulator body, then heating the glazed insulator body to the temperature of the melting point oi. antimony, and applying antimony in a fluid state to the insulator body while the latter is maintained at said temperature of the melting point of antimony, approximately from 1250 F. to 1300 F.

'I. The method of coating a porcelain insulator body which consists in first firing the insulator body, then heating the insulator body to a temperature of approximately from 1250 F. to 1300 F., and applying antimony in a fluid state to the insulator body in a reducing atmosphere.

8. The method of coating a porcelain insulator body which consists in first firing the insulator body, then heating the insulator body to a temperature of approximately from 1250 F. to 1300" F., and maintaining the insulator body at such temperature for about one hour while applying antimony in a fluid state thereto in a reducing atmosphere.

9. The method of coating a silica-containing insulator body which consists in first firing the insulator body, then heating the insulator body in the presence of volatile antimony in a reducing atmosphere.

10. A silica-containing body having a coating of antimony that has an integral molecular union with the silica-containing body.

11. A porcelain body having a coating of antimony that has an integral molecular union with the porcelain body.

12. The method of coating a porcelain body which consists in first firing the same, then heating it to the melting point of antimony, and applying antimony in a fluid state to the porcelain body while maintaining the latter at the temperature of the melting point 0! antimony, approximately from 1250 I". to 1300 l".

LAURENCE J. DYKSTRA. EDWIN M. MEYER. 

